The oldest lighthouse in New York, Montauk was completed in 1796 and became "the most important landfall light for ships bound for New York City from Europe" during the first half of the 19th century, according to a U.S. National Park Service statement.

In general, National Historic Landmarks are chosen "because they possess exceptional value or quality in illustrating or interpreting the heritage of the United States," according to the Park Service, which administers the program on behalf of the Secretary of the Interior.

With the new additions, there are now about 2,500 historic landmarks, "places [that] not only showcase our rich and complex history—from prehistoric time right up to the modern era—but [that also] help drive tourism and boost local economies," Park Service Director Jonathan B. Jarvis said in a statement.

Mark Vigil, chief of the San Luis Obispo County Chumash Council, peers into a cave once inhabited by prehistoric peoples in the Painted Rock monolith in a 2000 photograph.

The 55-foot-tall (17-meter-tall) rock formation is one of a hundred such sites within the 250,000-acre (101,000-hectare) Carrizo Plain Archaeological District, located between Bakersfield and San Luis Obispo, California (see regional map).

Painted Rock and other pictograph sites within Carrizo "represent what is probably one of the largest and best concentrations of painted rock art in the U.S.," according to the National Park Service.

The William H. Danforth Chapel (pictured in 2010), on the Florida Southern College campus, is part of the largest "integrally designed" grouping of Frank Lloyd Wright buildings in the world.

"The significance and beauty of [the campus] does not lie in any single building, but rather in the sum of the parts," according to a National Park Service statement.

Between 1938 and 1958, the college implemented Wright's vision of "organic architecture"—ten buildings of various sizes and functions, a large water feature called the Water Dome, and about 1.5 miles (2.4 kilometers) of covered walkways known collectively as the Esplanade.

In June 1876, Native American medicine man Sitting Bull received a prophecy of tribal victory at the Battle of the Little Big Horn—a vision he etched onto Montana's Deer Medicine Rocks, seen above in 2008.

Approximately two weeks later the Lakota, the Northern Cheyenne, and the Arapaho did indeed win the fight against Lt. Col. George A. Custer's Seventh Cavalry.

The site is now unique, in that it provides a Native American interpretation of the famous battle, according to the National Park Service.

Meadow Brook Hall in Rochester, Michigan, (pictured in 2007) is "an outstanding example of a 20th-century American country estate," according to the National Park Service.

Though the mansion and its grounds are inspired by English architecture, original owner Matilda Wilson felt strongly that its materials and builders be all-American.

Wilson later donated the property to the University of Oakland, and since then the school has used the estate for a variety of purposes while maintaining its original character, according to the Park Service.

The U.S.S. Slater is pushed down the Hudson River by the tugboat Herbert P. Brake from Albany, New York, to its winter berth at the Port of Rensselaer (see map) in 1994.

As a destroyer escort, the U.S.S. Slater accompanied convoys of supply and troop ships to Europe and around the Pacific toward the end of World War II.

Restored in 1991, the ship is "nationally significant for its outstanding associations with American naval strategy and operations during World War II, and as a rare and extraordinarily intact example of an important class of mass-produced warships designed for convoy protection," according to the National Park Service.

New York City's Town Hall was built in 1921 specifically to foster civic education and debate.

From the building, the League of Political Education broadcast the weekly show America's Town Meeting of the Air from the 1930s to the 1950s—"the golden age of network radio," according to the National Park Service.

The radio show followed the model of the New England town meeting, airing speakers who debated many issues in American life. The program set itself apart by allowing the audience to participate live—a "significant innovation in American broadcasting," according to the Park Service.